The United States National Reconnaissance Office has launched a classified satellite into space as part of the country's national defence efforts.

The United States National Reconnaissance Office has launched a classified satellite into space as part of the country's national defence efforts.

The satellite was carried on board an Atlas 5 rocket, which launched successfully from California at 2:39pm PDT, after having initially been delayed six weeks due to equipment problems.

A webcast of the launch was available to view, but the image was cut as soon as the launch ended, in order to protect the secrecy of the mission. One might wonder why the event would be announced and the launch shown, but this helps confirm the US' ability to add more satellites to its defence arsenal, the public announcement of which could act as a deterrent to opposing governments.

This is the fourth satellite launched by the National Reconnaissance Office this year, designed to gather intelligence. Nothing else is known about the satellite or its mission.

11 tiny Cubesat satellites were also launched with the larger surveillance one, designed to conduct research on space weather and track maritime shipping containers, among other subjects. Some of these are for the US Army or NASA, while others are for research by universities throughout the US.